Follow-up to r1113: Reset OpenSSL thread-safety callbacks when apr_terminate() called. Otherwise serf crashes on application exit on Windows.
Follow-up to r1113: Reset OpenSSL thread-safety callbacks when
apr_terminate() called. Otherwise serf crashes on application exit
on Windows.

Approved by: Justin Erenkrantz

* buckets/ssl_buckets.c  
  (init_ssl_libraries): Register pool cleanup callback in ssl_pool.
  (cleanup_ssl): Reset OpenSSL thread-safety callbacks.
jandre/serf,jandre/serf,jandre/serf,jandre/serf